diff -r 000000000000 -r 7f95f8617b0b vendor/doctrine/lib/Doctrine/ORM/Query/Expr/Base.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/doctrine/lib/Doctrine/ORM/Query/Expr/Base.php	Sat Sep 24 15:40:41 2011 +0200
@@ -0,0 +1,85 @@
+<?php
+/*
+ *  $Id$
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the LGPL. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\ORM\Query\Expr;
+
+/**
+ * Abstract base Expr class for building DQL parts
+ *
+ * @license http://www.opensource.org/licenses/lgpl-license.php LGPL
+ * @link    www.doctrine-project.org
+ * @since   2.0
+ * @version $Revision$
+ * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
+ * @author  Jonathan Wage <jonwage@gmail.com>
+ * @author  Roman Borschel <roman@code-factory.org>
+ */
+abstract class Base
+{
+    protected $_preSeparator = '(';
+    protected $_separator = ', ';
+    protected $_postSeparator = ')';
+    protected $_allowedClasses = array();
+
+    protected $_parts = array();
+
+    public function __construct($args = array())
+    {
+        $this->addMultiple($args);
+    }
+    
+    public function addMultiple($args = array())
+    {
+        foreach ((array) $args as $arg) {
+            $this->add($arg);
+        }
+    }
+
+    public function add($arg)
+    {
+        if ( $arg !== null || ($arg instanceof self && $arg->count() > 0)) {
+            // If we decide to keep Expr\Base instances, we can use this check
+            if ( ! is_string($arg)) {
+                $class = get_class($arg);
+
+                if ( ! in_array($class, $this->_allowedClasses)) {
+                    throw new \InvalidArgumentException("Expression of type '$class' not allowed in this context.");
+                }
+            }
+
+            $this->_parts[] = $arg;
+        }
+    }
+
+    public function count()
+    {
+        return count($this->_parts);
+    }
+
+    public function __toString()
+    {
+        if ($this->count() == 1) {
+            return (string) $this->_parts[0];
+        }
+        
+        return $this->_preSeparator . implode($this->_separator, $this->_parts) . $this->_postSeparator;
+    }
+}
\ No newline at end of file